Elevator



Jan; 5, 1943.

c. H. BOND ELEVATOR Filed Dec; 13, 1940 6 Sheets-Sheet 1 Snvenl-or.

I C'lini'on 77. Bond. W

4 A mg.

C. H. BON D Jan. 5, 1943.

ELEVATOR Filed Dec, 15,1940 6 Sheet s- -Sheet 2 3nventor C'Zinton 7"/.Bond,

C. H. BOND Jan. 5, 1943.

ELEVATOR Filed Dec. 13, 1940 e Sheets-Sheet s.

Unventor. C'Zz'n' fan 7/.Bond.

c. H. BOND ELEVATOR J Jan. 5, 1943.

6 Sheets-Sheet 4 Filed Dec. 13, 1940 t to meg c. H. BOND Jab. 5, 1943.

ELEVATOR Filed 15%. 13, 1940 'GSheetS-Sheet e say 90 12,: u

3maentor Bond,

vice positioned above the car. larged elevation of a vertical pair ofspaced rails Patented Jan. 5 1943 UNITED STATES PATENT OFFICE ELEVATORClinton H. Bond, Cedar Falls, Iowa, assignor to The Wagner ManufacturingCompany, Cedar Falls, Iowa Application December 13, 1940, Serial No.369,963

7 Claims. (Cl. 187---31) My invention relates to improvements inelevators and their mechanisms, including electric circuits therefor.

A principal object of my improvements is to employ means for insuringsafety of the passen- Another object of my improvements is in supplyingassociated devices for stepping down the speed of the motor, with othermeans including a plurality of dash-pots for dampening jars incident tothe to and fro actions of the motor connections during itsreciprocations of their linked elements.

Another object of my improvements is the combination of offset car andshaft doors, whether in a single cooperating pair for opposite shifting,or in two sets of pairs for like purposes, as desired, and in both ofwhich pairs or sets certain of the pairs travel to and fro at differingspeeds, conducive to the safety of car occupants, or when entering'orleaving the car.

Other improvements will be shown and described herein, and it is to beunderstood that various modifications may be employed without departurefrom the scope of the invention to be defined in the claims.

The different featuresof my invention are depicted in the appendeddrawings, in which:

Figure 1 is a View, partially in side elevation and in longitudinalsection, of the electric motor and its accessories, with parts brokenaway. Fig. 2 is a front elevation of the above, also with parts brokenaway. Fig.3 is a top plan'ofa frame "de- Fig. 4 is an enand showinglinked connections to one rail as associated with said electric motor,parts being broken away. Fig. 5 is a fragmental top plan of .frameelements shown in :Fig. 4, with parts in section, and Fig. 5a is atopplan of one of the coiled springs bearingagainst the movable railaforesaid. Fig. Bshowsa vertical plane member .of said doors.

on which is mounted a braking stop adapted to be positioned between thefixed and movable parallel rails thereon, the figure including 'a.make-and-break device operatively linked to jointed rock members, ofwhich one member has said braking stop thereon. Fig. 7 is a verticaledge elevation of the elements shown in said Fig. 6, with parts brokenaway, and Fig. 8 is a fragmentary :top plan, in partial section, of theelements shown in said Fig. 6. Fig. 9 is an elevation of one face of adoor of this invention,

with parts broken away or removed, showing braking means thereon, and vdamping means mounted movably on the door and having a flexibleconnecting element connected to a rockable arm on the reciprocatoryelement shown in Fig. 2. Fig. 10 is ahorizontal cross section of thespaced parallel car and corridor doors, including a braking device onthe latter, and also showing upper parts of other elements as partiallybroken away, being parts of pairs of slidable doors without said:elements, the view including also relatively fixed frame parts withbuffers thereon and cushioned to receive impacts thereon Fig. 11 is anelevation of an open .outer :frame and of a car positioned thereincarrying the reciprocatory member mounted on the .motor, withconnections to one of said pair of :fixed and movable rails in relativeadjustment. Fig..12 isfa side elevation ofthe structures shown in :saidFig-11, with parts broken away. Figs. 13 to 16 inclusive are enlargeddetail viewsof certain subordinate devices of my invention, described asfollows: Fig. 13 is an elevation of a housing member mounted on a bodyframe carrying an .electric motor. Fig. 14 is a .top plan of saidhousing .memberwith top removed. Fig. 15 is a side elevation :of thehousing shown in Fig. 13,

and Fig. 16 .is a vertical cross section thereof.

Fig. 17 is a diagram of the'motor circuit, and 'Fig. 18 is a partialdiagram of the-circuit having a plurality of openable electric contactsalined therein.

Referring to Figs. 1 and 2, the numeral I 'denotes a rotary motor whichhas wiring terminals :11, yandz leading in a circuit as shown in Fig.17.

The motor shaft 3 traverses a bearing seat in a face-plate 4 of themotor, and -a smallbelt-wheel 9 is secured ona stem 8 secured on theshaft 3. Asupporting frame body '6 is secured by'screws -5 toa rimofsaid face-plate 4. Between parts of said frame 6 are sockets :thereinseating the ends .of a shaft carrying a relatively large "diameterbelt-wheel H]. A T be'lt 9a is reeved on the wheels 9 and ill. A'smallbelt-wheel Ila ison an enlarged part of the shaft II. A shaft I3 ismounted in the frame part 1, and carries thereon a belt-wheel I2, and abelt is reeved around the wheels Ila and I2. The frame part la isapertured to seat therethrough a shaft I3 carrying on its outer end parta relatively small spur-gear I4. The right-hand end part of the shaft IIis seated in a cupped removable cap I! secured to the frame I by screwsI8.

The frame 1 projects downwardly, and its lower part is transverselybored as a seat for a transverse shaft I 9 fixed therein removably. Thelefthand part of the shaft I9 is diminished in diam eter at Isa, hasseated thereon a washer 2Ia, a thicker washer or nut 2| extendingoutwardly and is terminally threaded to seat two nuts 22 and 23 thereon,with a compression spiral spring 20 between the said nuts and thefirst-mentioned nut 2i. A threaded plug IElc is seated in a threadedhole in the frame for permitting lubrication. A band ring I91) ismounted as a spacer on the shaft I9 which projects forwardly through arocker body I5, and carries on its outer end a bar 39 which is mediallypivoted, with a securing end nut.

The rocker body I is widened at the top with the upper marginal edgebeing curved, and an arcuate plate I5a is removably secured by bolts I5bin its lower part upon the body I5 to extend .a short distancethereabove, with the extended part having equal length arcuate slots I50therein traversed by bolts I5d and I Be in each case having end nutsthereon, whereby when the bolts are adjusted along the slots I50 and I5hrespectively,

th nuts may be turned to secure the bolts in place for variations oftheir positions.

The curvate part I5a has an arcuate depression seating the spur gear I4therein to mesh with teeth I5c as shown in Fig. 2, for rocking thesegment I5a together with the depending member= I5 to and fro a limiteddistance in a medial curvate path. The lower rock body part I5 isrockably mounted on the transverse shaft I9, and

there is a bolt and nut connection at I9d between the elements I5 andthe depending part of the bar 39. Just above the connection Ifld thelower part of the member I5 has an arcuate slot I5g, with screw seats 38at its ends, to seat screws at times. In the lower end of the bar 39 isa pivotal connection 391]. with one end of an arm 40.

An upper offset part in of the body 1 serves as a supporting base for acasing 28 mounted therein by basal screws, removably. The casing 28 ispositioned in an upwardly opening seat between oppositely directed sidelugs 35b (see Fig. I

2), which are apertured vertically as shown by dotted lines, and on theside parts of the frame I in the rear wall thereof are mounted, as shown:by full and dotted lines, a like spaced pair of vertical tanks 35having filler tubes 35a, capped to 16, respectively, the casing 28hereinbefore alluded to, has a face-plate 28a secured thereto by screws28b through side flanges. A forwardly bent riser 29 is secured by screwsto the upper projecting part of the front plate 28a. A stem 30atraverses a bearing hole in said riser being loosely seatedtherein. Theupper end of the .stem carries a compression coiled spring 300 aroundit. Spring 30 bears at its lower end upon when the rocking actionceases. .combined members I5a and a bifurcated head fixed on the lowerend of the stem. A pintle 3Ia rotatably seats in the bifurcations andhas a roller 3I thereon. A rock-shaft 24 traverses medial aperturedseats in th front and rear walls of said casing (see Figs. 13 and 15),and a tripartite arm device is fixed on the forward end of said shaft todepend vertically downwardly.

The tripartite arm or member referred to has a medial depending angularfinger 25 with like but relatively reversed lateral like curvilinearlydownwardly directed terminations with curvate outer edges as shown inFig. 13, these curvate edges medially of the device being joined at anangular depression. This axis of the device lies closely below theroller 3I which rides rockingly to and fro on the members 26 and 21, theroller being seated in the reentrant angle between the side members whenthe member 25 is in a vertical position, where it is yieldingly held bythe spring 30 acting on the roller.

Fig. 14 shows the casing 28 with the front cover removed. The shaft 24has its forward end seated rotatably in an adjustable apertured bodyhaving an adjusting pin 24a. Medially spaced angle-bars in pairstransversely spaced apart and spaced from each other, as at 2817 and280, 28f and 281 are bolted upon the inner rear face of said casing.Like but reversed resilient bars 28d and 28a are positioned in parallelrelationship in the casing 28 and are spaced from the upper and lowerfaces of the flanges of the angle-bars, the left-hand end parts of theresilient bars being seated in depressions of the flanges. The righthandend parts of the resilient bars 28d and 28a are spaced from the flangesof the angle-bars, with blocking members engaged therebetween. Headedpins 33b and 330 with heads adjacent to each other traverse apertures inthe resilient bars 28d and 28e, with coiled compression springscontacting at one end with said bars, and preferably with washerscontacting with the opposite ends of the springs, the remote ends of thepins being apertured to seat therethrough split-keys as at 28. Fig. 16shows in left-hand elevation and section equivalent features of some ofthe elements shown in Fig. 14. Fig. 15 is a top plan of the casing andits front plate or cover 2828a, showing for convenience, an end cap 29therefor permitting inspection of the interior.

Referring again to the rocker element members -25 to 21, it will be seenthat in Figs. 1 and 2 is shown a recess I51 in Fig. 1, into whichdepends rockingly for loose contact the medial tongue part 25, which isrockable to and fro, and acts to produce like movements in the rockmembers I5a and I5, limited by adjusting bolts I5d and I5e. The laterallike but relatively reversed side members 26 and 21 act as cams as theroller 3I rides thereover under the light compression of the spring 30.It will be seen that at either of the terminal movements of saidmembers, as adjusted by the bolts l5d and I5e, the action of the spring30 will cause a rocking return movement of the device into its medialdepending position In this way the I5 are rocked together to and froduring the action of the pinion I4 in likewise rocking to and fro, toalternately reverse the rocking of the rotor in the housing I, while theelectric circuit shown in Figs. 17 and 18 is closed, and when thecircuit is open, the driven members hereinbefore mentioned are returnedto their initial medial positions. The incased devices within thehousing springs a fixed arm 88 projects to the left and 28 act asauxiliary controlling means in stabilizing movements of the combinedrock bodies I and I M, and of the medially pivoted rock-arm 39 with itsconnecting means at 4| to one or the other of pin sockets 42 in thelinking member 43,

as is also shown in Fig. 4, where screw plugs are shown. In Fig. 11 isshown an equivalent conneoting means between the rocker member 39 at thetop and the rock body I5, being an offset arm as shown.

The numeral 6'! denotes a slidable door for the open front of anelevator car It in which car is movably seated an outer slidable doorI00, termed a shaft door. These relatively slidable doors have mountedon their opposed inner faces certain fixed and movable contrivances, tbe hereinafter described, and shown on a reduced scale in Fig. 11. Fig.4 shows on a larger scale certain contrivances or movable and fixedassociated elements, as follows.

The bar link 40 has i its outer end pivoted at 4! in one of the socketsin a fixed bar 43, and usually in the uppermost socket, the othersockets having screw closures 42 therein for adjusted connection to thebar 43 as desired. Adjacent to one leg of a vertical angle bar 53 (seeFig. 4), and on a rectangular plate 54 is secured at each of the upperand lower edges like bars 54a. and 69 seated in brackets shown at 55,55, 6! and 52. The plate 54 is secured to the inner or car door 51.

Vertically spaced bracket arms 54 are fixed on the brackets 55 and GIand are supported loosely by fixed pins 63 and 53a respectively. Coiledcompression springs 65 and 65a are mounted upon pins 63 and 63a.

The numeral 41 denotes a vertical angle bar fixed by bolts 48 on thesaid door 61. A flat their supports are shown in superposed relation inFigs. 5 and 5a. Fig. 11 shows a metallic skeleton open housing or framewith vertical transversely spaced standards secured at their lower endsbetween flanged members 15 fixed below and in contact with a flooringT4. The upper ends of the standards are fixed to and between horizontalflanged bars 59 and 12 by bolts traversing the flanges of the bars I2and 69. Upon the forward face of the forward angle bar 12 is mediallymounted between the side bars 69 the electrically controlled motor I andits associated fixed and movable contrivances shown n Figs. 1 and 2.

Referring to Figs. 4 and 9: In Fig. 9 is shown the door 67 a Verticallyspaced pair of like arms I8 and 92 respectively pivoted their upper endson studs 11 and 9I, with the lower end parts slightly deflected to theright vertically. The lower part of the upper arm 58 has a diminishedtermination 89, and just above this the arm is pivoted at 79 to a bar82, flanged at one side and having its base secured to the door byscrews. A headless screw BI traverses the longitudinal flange andend-engages the finger 89 adjustably. In depending alinernent below theangle-bar 82 is a channel bar 83. abutting the angle-bar has fixedthereon spaced angle members 85 and 85 connected by a rod, and coiledsprings 81 are engaged between the angle members, between which members.and

,A liner plate device 84 has a terminal angled head 89 secured to achannel bar 90. The member 83 is linked to the upper end of a flexiblewire rod 65 whose lower end is passed through a fixed loop 'H on themember 39. The wire rod or member 65 has its upper end secured to thechannel bar I2 after traversing the loops spaced along the arm 39. Theswingable arm 92 (Fig. 9) and connections pivoted at the top at 9| andat 94 to a plate 93 are like the upper arm devices at E1 and I8, andmaintain them both in vertical alinement, while the springs 81 brake theend movements of the arm 39.

Referring now to Figs. 6, 7, 8 and 10, and particularly to Fig. 10: inthe latter are shown the opposite spaced parallel car and shaft doors 61and I953 as seen from above and both in horizontal section. On the faceof the car door 51, in top plan, are shown certain related membersdisplayed on Fig. 11 and already described herein, including in crosssection the members 49 and 53, relatively fixed and movable. On theopposed shaft door (m9) and shown in Figs. 6, 7 and 8, are certainmembers, including an offset plate I46 projecting above the top of thedoor I90 and on which is mounted a casing I34 having a side slot I3 ia.Within this casing is a bifurcated body I43 opposite said slot w ld androckable upon a pivot M2. The body I43 has an angularly directed arm I44carrying a roller I i-5 on its remote end. Also within said casing abovesaid slot is a fixed bracket I35 carrying a medial projection I36. Likebut reversed pointed and relatively ofiset projections I37 and I38 areon the bracket I35 and both spaced from the projection I35. Like butspaced spring fingers I39 and I49, bent away from each other, are fixedon the part I35 with small coiled springs Id! bearing against thefingers.

An arm I24-i2'5 has a medial boss I25 pivoted on the offset upperportion of the plate Hi6 with the lef -hand channeled portion of the armpositioned between a pair of rubber sleeved pins I23 and rockable to orfrom either pin. The opposite part of the arm at I25 has a terminal hookIZIia which as shown in Fig. 6 traverses the slot 834a in the casing I3l in a lowered position and has its end hook lockably engaged with thecasing part below. In this position, the hook depresses the lower fingerof the part M3, causing the rocking of the rigid arm IM to force theroller I45 between the spring terminals I39 and Spaced beneath the platei2! is a flat plate It! secured by screws lIIa to the lower part of thedoor I69 below the offset upper plate 12!. A bar I20 may (or not be)secured at its opposite ends by screws or other means to and betweensaid plates.

A rock arm 453 has its lower end pivoted at I98 to the lower right-handcorner part of the plate Ill, and a shorter arm I52 is also pivoted onthe same pivot as the arm I03, and secured to the latter by a screwIIlZa. The arm I92 has at its outer end an interiorly threaded boss to.seat thereon a rotatable and preferably rubbercovered cylindrical headI95. An offset arm I9I has its lower end pivotedat I04 to the outer endof the rockable arm I93 and extends upwardly therefrom. The two arms NHand IE3 are always directed to the right at their pivotal connectionrelative to each other. The upper end of the arm IIII is pivoted at I21to the arm part I26. On the rear face of the upper part of the arm ml isa stud I29 to which is anchored an end of a resilient rod 128, which ismedially coiled on a stud I28a on the arm 141, the latter being rockablethereon, and tending to yieldingly and normally keep the arm lill in itsremote position to the right, as shown in Fig. 6. A resilient offset barlll'l secured on the plate H! crosses and serves to brake the movementsof the arm part I02.

Fig. '7 shows a side elevation of the door 100. A pair of screw hangersI54 on the upper end of the door I carry a C-shaped tubular member I52within which is rotatably pivoted a channeled wheel I53 ridable along arail ll bracketed at I50 to the depending end of a hanger I54a. By thismeans the door if! may be shifted horizontally.

In Fig. is shown in horizontal cross section the car door 51 and theshaft door Hill spaced in parallel relationship. The roller MS (as shownin Fig. 7 and in Fig. 6), is shown between the fixed and movableangle-bars l-5El and 53, in contact therewith. The numerals H8 and H9denote spaced stepped moldings, spaced apart rigidly, and having fixedon opposite steps thereof rubber pads I09 and H9 respectively. Thesepads prevent clashing and noise during the operation of the doors at alimit of travel. Referring to Fig. 10 again; a supporting member H2 ismounted on the cab door 5? when desired, and has a rigid arm H3 spacedparallel and apart from the door, and cross-connected loops of metal H4and 4a together with said arm H3 are traversed by a securing pin. Asingle loop H5 of metal is secured to and projects in alinement from theassociated parts E E4 and i Ma, and is covered by a yieldable flexiblecover H6 of U-shape whose terminations are also secured between theparts H4 and lla. his device projects a short distance beyond and inalinement with the supporting means H2 and H3, serves as a resilientbuffer beyond the edge of the door 67 and is adapted to push away aperson trying to slip into or out of the car without injury.

When the parallel doors 6'! and H19 are associated by means of theengaging elements 5349 having the rubber covered roller Illfi graspedbetween them, the pair of doors may be shifted horizontally together.The doors are disengaged by the motion of the car up and down, therebyremoving element I35 from between elements 49-53. In Fig. 10, additionalor auxiliary offset pairs of doors 9691 and 9899 may be supplied forhorizontal movement together or in conjunction with the pairs of doors6'! and 500, without departing from the invention herein.

Fig. 17 is an electric diagram including a reversible electric motor andconductors with makeand-break devices in the circuit, and leads to apower supply not shown. Figs. 1 and 2 show the leads to and from themotor as broken away. The diagram is explained as follows: Theconnections and contacts are as shown when the car is moving with doorclosed. The operation is explained as follows.

The contacts A and B on the elevator controller are to be mechanicallyinterlocked. The contacts A close, and the contacts B open when the carcomes to a full stop deenergizing the coil B-I The limit switch contacts0 open when the doors are fully open. The contacts B close, and thecontacts A open when the button is pressed, energizing coils 3-! toclose doors. The limit switch-contacts C open when the doors are fullyclosed. The car must not leave the floor until the gate contact isclosed. The closing of con tacts ST connected to the safety stilecompletes the circuit through time relay TR, which breaks the contactT2, which stops the closing of the doors and closes contacts T-I, whichenergizes the coil A--l, and which opens the doors again. After a timeinterval of approximately fifteen seconds the time relay closes contactsT--2 and opens contacts T-l allowing the doors to close. The push buttonPB, located in the car, operates the same way as the safety stile.

Symbols Normally closed Cab circuit Fig. 18 is a diagram of a carcircuit, having a car gate contact and an emergency release switch E,together with a plurality of ordinarily open contacts in number equal tothe fioors of a building. This circuit F provides a make-and-breakcontact at each floor. In the event that the car cable becomes entangledbetween floors, the operator at the interlock thereof between floors mayclose a contact there, as shown in Fig. 18 in the elevator emergency carcircuit, whereby the cable is released from the impediment.

I claim:

1. The combination with an open front elevator car mounted for verticalmovements, of door closures therefor, relatively spaced and offset fromeach other, a vertical pair of parallel spaced bars abutting the outerface of the inner closure with one bar mixed thereon and the other barmounted on the face in movable contact therewith and for horizontalmovement toward and from the fixed bar, a laterally movable singleprojection having a rotatable cylindric head on the inner face of theouter closure and adapted to extend between the bars in spaced relationthereto, a swingable device extending into the interspace of theclosures and terminally linked to the movable bar, whereby when thedevice is rocked in one direction said movable bar and fixed bar contactopposite sides of said cylindric head, and when said device is rockedoppositely the projection is freed from said contacts and means mountedon the outer closure for releasably locking the swingable devicethereto.

2. The combination with an open front elevator car mounted for verticalmovements, of door closures therefor, relatively spaced and offset fromeach other, a vertical pair of parallel spaced bars abutting the outerface of the inner closure with one bar fixed thereon and the other barmounted on the face in movable contact therewith and for horizontalmovement toward and from the fixed bar, a laterally movable singleroller device mounted on the inner face of the outer closure and adaptedto extend normally loosely between the bars in spaced relation thereto,and a swingable reversing motor device having a pivoted and swingableconnection with the movable bar device to contact the single roller withand between said bars releasably.

3. The combination with an open front elevator car mounted for verticalmovement and for halting its movement at determined stages, of doorclosures relatively spaced and one offset from the other for lateralmovement, a vertical pair of parallel spaced bars abutting the outerface of the inner closure with one bar fixed thereon and the other barmounted on the same face in movable contact therewith and for horizontalmovement toward and from the fixed bar, a roller device having anelastic tread and mounted on the inner face of the outer closure andadapted to extend between the bars in spaced relation thereto, and meansfor releasably engaging the roller with said bars consisting of aswingable arm, means for limitedly swinging the arm, a link having oneend pivoted to one end of said arm and having its other end adjustablypivotally connected to the movable offset door closure.

4. The combination with an open front elevator car mounted for verticalmovement, of a pair of spaced parallel car and shaft doors mountedslidably on the car with separable connections between their opposedinwardly directed faces, and a buffer bracket with a resilient headmounted on the forward inner part of the car door parallel therewith andprojecting beyond the front edge of said door.

5. The combination with an open front elevator car, of a pair of spacedparallel car and shaft doors positioned at the open front of the car,with the car door shiftable horizontally, parallel spaced vertical barspositioned on the car door, one bar being fixed thereon and the otherbar removable to and from the first bar limitedly, spaced resilientdevices mounted on the first door to bear against said movable baradjustably, a rock arm mounted on the first door pivotally andadjustably, a swingable arm on the rock arm, mechanism mounted on thecar and linked to the swingable arm rockably, a rock arm mounted on theinner face of the shaft door, means on said door for limiting the swingof the rock arm in one direction, and a roller mounted on the rock armand extending between said fixed and movable bars for either loose orengaging contacts.

6. The combination with an open front elevator car, of spaced relativelyslidable doors therefor, an electric motor mounted fixedly on the car, aframe device rigidly bracketed on the motor housing, coacting step-downdevices in train with the motor shaft including a toothed pinion, arock-body mounted on the frame device for adjustable rocking movement,the rock-body having arcuately arranged teeth thereon in mesh with saidpinion, an arm limitedly rockably adjusted on the rock-body and securedthereto, linking bodies connected adjustably to the car door of the pairmovably, means on the shaft door of the pair for releasably connectingthe latter door to the former door, a tripartite member limitedlyadjustably rockably mounted on said frame and positioned mediallythereon, a spring controlled roller on the frame to ride upon and alongthe upper and medially indented parabolic edges of the side parts of thetripartite member as the latter rocks to and fro, and the medial angularpart of the member being rocked by the rock body, the electric circuitcontaining make-andbreak devices and in communication with said motor,and with a source of power supply.

7. In combination, a vertically movable elevator car, with an openfront, oppositely spaced parallel car and shaft doors positioned forclosing said open front, spaced vertical parallel bars mounted acrossthe outer face of the car door, one bar being fixed thereon and theother movable to and from the fixed bar, the fixed bar having acushioning strip fixed along its face opposite to the movable bar,resilient devices having their outer ends connected to the car door withtheir opposite ends bearing against said movable bar, mechanism forshifting said bars toward each other, controllable stop devices rockablyand releasably lockably mounted on the rear face of the shaft doorincluding a roller thereon movable to enter between said barswithdrawably when the bars are moved out of contact with the roller.

CLINTON H. BOND.

